In a recent semiconductor integrated circuit, much higher-speed signal processing is required, and a laser light emitting device is being used to transmit the signal between circuits. Particularly in a semiconductor integrated circuit, there is a strong demand for implementing a Si or Ge laser light emitting device that can be formed on a Si or Ge based semiconductor substrate. Therefore, there has been made a proposal in which a Si nanocrystal is used (see Patent Document 1) or a proposal in which the light is emitted by utilizing a Si waveguide on the Si substrate.
However, in each proposal, only spontaneous light emission from the Si crystal can be confirmed, and the laser oscillation is not achieved yet by utilizing the Si crystal.    Patent Document 1: Japanese Patent Application Laid-Open No. 2001-040348